Electrical connecter



July 12, 193s. C. H. KQEHLER 2,123,631

ELECTRICAL'CONNECTER Filed July s, 1955 3 sheets-sheet 1 Wiz/"M July v12, 193s.

c. H. KoEHLER ELECTRICAL(r CONNECTER med July e, 1955 3 Sheets-Sheet 2 July 12, 1938. Q KOHLER 2,123,631

ELECTRICAL CONNECTER Filed July 8, 19.35 3 Sheets-Sheet 3 tially floating engagement therebetween.

Patented July 12, 1938 UNITED STATES PATENT oFFlcE 14 Claims.

This invention relates to electrical connecters, and more particularly is directed to connecters providing a positive electrical connection between two spaced contact terminals, and capable of maintaining an equalized contacting pressure at both contact terminals regardless of slight misalignment of the terminals.

In my copending application, Serial No. 724,118, led Mayf, 1934, now Reissue Patent No. 20,608, dated December28, 1937, I have disclosed a plug and receptacle connecter lparticularly adapted for connecting and disconnecting an electrical circuit, havingy a `plurality ofv contact shoes mounted for universal movement about a terminal stud and adaptedto engage about a contact stud carri`ed\,by amovable closure member.

The present invention; in Vits preferred embodiment, is directed tov af'similar connecter mounted on a xed terminal stud which is connected to a second spaced contact terminal by means of an extending connecter having substan- This accommodates any slight misalig'nment between the terminals. Engagingeach of the terminals is a plurality' of contact shoes having substantlally universal movement about .the terminals and normally urged .under spring pressure against the terminals' andalso against the connecter.

An object of the present invention is to provide a connecter fory electrically connecting two spaced s contact'. terminals,` which connecter has relative oating engagement between .the terminals to accommodate slight misalignment therebetween, -v

lAnother object o f the. present invention 'is 4to maintain equal contactpressure between the terminals and the contact shoes, and ebetween* the shoes and the-connecter. yThis :equalization of pressure obtainedby the provisiony ofxa yfull.- oating housing enclosing the shoes and biasing the outer-ends ofthe springs associatedywith each of the shoes, or by the provisionI of anintermediate spider'member having, arms upon which the shoes are mounted 4for substantially universal spring-controlledgmovement. ,y

Another object Vof "the present invention is the elimination of spring means from any 'part'of the electrical circuitthrough the'contact" te# minals, whereby thelie of thel springs'is materially increased.

' In the Aprovision of a disconnecting device or connecter for connecting and disconnecting two spaced terminals, spacial requirements usually demand a compact but sturdy construction. The present invention nds particular application for l present invention; i FigureZ is an enlarged plan Vterminal contact devices, taken substantially on of Contact shoes;

such use and produces a high-grade efficient contact device. Also, because of its self-aligning characteristics, the present invention is capable of being employed in connection with the terminals of circuit breakers, if desired, since the 5 sockets or terminals of such"v breakers must be self-adjusting and capable of maintaining equalized contact pressure upon the male contact plugs with which the breaker terminals are engaged when the breaker is connected in switch-closed 10 position. It is to be understood, however, that the invention is `not to be limited to these specic uses, since the'broad features thereof are applicable in various other iields.

Other objects and advantages of the present invention Vwill appear more fully from the following detailed description which, taken in conjunction with the accompanying drawings, will disclose to those skilled in the art the particular construction and operation of a preferred form of the present invention.

In the drawings:

Figure v1 fs an elevational view, partly in section, of an electrical connecter embodying the 25 view of one of the line 2--2 of Figure 1;

Figure 3 is a plan' view of a modied form of contact structure;

Figure 4 is a view, on a smaller scale, taken through the structureV shown in Figure 3, with the connecter inserted; Y `Figure 5 is a vertical sectional view through a modifiedform of connecter; fj'

' Figure 6 is a plan viewI of amodied assembly Figure 7 isaxsectional view throughfa-still further modified type of-connecter;

. Figure 8 `is -a vvertical sectional view through `4,0

a telescoping type ofy connecter` embodying rthe principles of the present invention;

Figure 9 is a sectional viewstaken on Figure 10 is a sectional View taken substantially 45 on Yline Ill-I0 of Figure 8; and y MFigures 11 and 12 are sectional views of modiy'fled types of contacts. r

tending portions of the studs 1 and 8.

Each of the studs 1 and 8 is provided with an enlarged rounded head portion I0 and I2, respectively, which head portions are joined to the flange portion of the stud by means of a reduced neck portion.

The stud 1 is provided with a contacting structure indicated generally at I3, comprising a plurality of contact shoes I4, preferably six in number in the illustrated embodiment of the invention, although it is to be understood that any desired number of contact shoes may be provided. These shoes are internally recessed atl one end, as shown at I5, to engage about the head portion of the stud 1, whereby substantially ball and socket engagement of the shoe members I4 about the head portion I0 of the s tud 'I is provided.

At their opposite ends, the shoes Ilare provided `with inwardly extending tapered surfaces I6, defining an inwardly tapering circular opening for receiving a connecting member. y The externallateral surfaces of the shoe members are provided with recesses. I1 as shown in Figure 1,

which recesses are tapered to receive the small ends of helically coiled spring members I 8, which spring members, at their inner ends, bea-r against the shoe members I I to urge the same into equalized contact pressure about the head portion I8 of the stud 1, and at their outer ends are biased against the defining walls of an enclosing housing member I9 which is preferably polygonal in shape, having as many sides as there are shoe members in the present embodiment of the invention, being in the form of an hexagonal tube extending axially ofthe stud member 1. This member I9 may be formed of insulating material Aif desired.

Thus a full-floating self-aligning contact receiving structure I3 is provided about the head. portion -I-Il of thestud, which has substantialuniversa] movement about the stud 1. By reason of the springs I8, each of the shoe members has substantially uniform contacting pressure with the stud whereby equalized contact pressure of the structure I8 with the lateral surface oi the stud 1 is provided.

The head rportion I2 of the stud member 8 has engaged. therewith a 28. which shoes have recessed portions at one end thereof, as shownat' 2 2, adapted to have beating engagement about the rounded stud I2,

- whereby the shoes are supported for substantially lziverlllfconjoint movement' about the stud head 28, in theiriaister-smfaces, are 'receos'ed'fas 'shown at 23 tofprovide suitable seating 4.portions-for helically coiledsprings 24,'which springs, at their outer ends. are biased against an enclosing tubular polygonally shaped member 2l corresponding to the member I8 of Figure 2. 'I'he shoes are thus resiliently maintained in pressure contact about the head y portion I2 of the stud 8, and are supported for floating movement thereabout due to the fact that the sleeve member 25 does not extend up to the flange of the stud and therefore floats about the head I2 with the -shoe members. Each of the shoes 20 is also provided with an inwardly extending contacting porplurality `of contact shoes tion 26, which contacting portion is adapted to have equalized pressure contact upon the lateral surface of a connecting rod 21, which rod is formed of a suitable metal member having a relatively high degree of conductivity, such as lindrical opening defined within the inner sur` faces of the shoe members Il to provide for contact between the shoes 20 and the shoes I4.

The connecting member or rod 21, at its upper end, is mounted within a suitable insulating handie member 29, or may be carried by any other suitable operating mechanism for projecting it through the stud 8, which stud is provided with a cylindrical axially extending opening 30 adapted to receive the rod 21, and throughv the cylindrical opening formed in the contact shoes 20 downwardly into engagement within the opening formed by the shoes I 4. It will be noted that the rod 21 has relative telescoping engagement with respect to the stud member 8, and the contact between the stud member 8 and the rod 21 is provided by the engagement of the inwardly extending portions 26 of the contact shoes 28 with the lateral surface of the rod. This provides a wiping contact of these portions of the shoe members along the surface of the rod, whereby clean and positive pressure contact of the shoe members with the rod is provided. Since the shoe members 20, at their opposite ends, have pressure contacting engagement with the head end I2 of the stud, which is connected to the contact` supporting bracket 6, it is apparent that the rod 21 is in proper equalized pressure contact with the bracket 6 so thatcurrent may be transmitted from the bracket 6 through' the rod 21 with a minimum of resistance.

It will be noted that the upper end of the stud 8 is provided with an outwardly flaring opening 32 so that the head end 28 readily guided into the interior of the stud member 8 for telescoping movement therethroughA 4when it is-desiredlto connect the contact brackets. 5 and 6.

Normally, when the rod has not been connected in position, the springs I8 bearing against tire tubular sleeve member I 9 will urge the upper ends of the shoe members I4 inwardly, and when the head end 28 of the rod is guided into the open end of these shoe members along the tapered surfaces Il, the shoe members are spread outwardly against the pressure of the springs I8 whereby an equalized pressure contact of each of the shoes upon the head endl! ofthe rod is providedg It is thus apparent vthat I have provided `an electrical connecter whereby the rod 21 may ,be,. telescoped 'with respectto one contact studand g/uided into electrical contact engagement .witha second spaced contact stud, the two contact studs having contact devices where-l I the surface of the rod at each of the contacts regardless of variations in the alignment between these contacts. 'I'he opening 30l in the stud 8 accommodates slight cooking of the rod 21 thereof the rod 21 may be.

in when the studs 1 and 8 are not in exact alignment.

In the embodiment of the invention shown in Figures 3 and 4, the contact bracket 5 has a contact stud 1 mounted thereon by means of the nut 9 threaded over the extending portion of the stud, the head portion i0 of the stud being adaptedto receive a plurality of .contact shoes having recessed portions 36 at `their lower ends adapted to engage about the head portion I0' of the contact stud 1 whereby substantially universal movement of the shoes with respect to the stud is provided.

Thev shoes 35, at their upper ends, are provided with outwardly flaring tapered surfaces 31 for guiding the end 28 ofA a contact rod or connecting rod 21 into engagement within the circular opening formed by the respective surfaces of the shoes. Intermediate the head portion l0' of the stud and the position which the head portion 28 of the rod 21 assumes with respect to the shoes 35, there is provided a spider member 38 having a plurality of radially extending arms 39. The arms are adapted to extend through enlarged openings formed in the shoes 35, and project outwardly of the external periphery of the shoe members to the tapered openings 40 formed in the shoe members. At their outer ends, the arms 39 are adapted to carry suitable cap members 42, which cap members provide for biasing the outer ends of the helically coiled spring members 43 against displacement outwardly of the ends of the arms 39, while the springs 43 are biased at their inner ends against the base of the tapered openings 40. The shoes are thus mounted for universal movement about the stud-member 1', and

are held in their respective cooperating positions by means of the spring members 43 mounted about the arms 39 of the spider 38.

In this manner the shoes may move outwardly to accommodate the admission of the head end 28 of the connecting rod 21, and an equalized pressure of each of the shoe members against the surface of the rod and against the surface of the head portion I0' of the stud is provided.

It is obvious that the maintenanceof equalized pressure and the'provision of a positive, high grade, eiiicient contact structure is provided with either the construction shown in Figures 1 and 2,

where an enclosing polygonally shaped housingis provided, or by the provision of a spider such as shown in Figures 3 and 4.'

In Figure 6 I have shown a further modified form of contact assembly, in which a plurality of contact shoes form a circular opening 62 into which a contact connecting member is adapted to extend, and are held in position by means of a coiled garter spring 53 engaged in a suitable groove 54 formed in the outer lateral periphery of the shoes 56. The shoes are provided, at one end, with the inclined tapered surface 55 for guiding a connecting rod into the socket defined by the shoes. The garter spring 53 is adapted to constantly urge the shoes toward each other, and radially inwardly toward the contact member, whereby equalized pressure of each of the shoes against the contact member is provided.'

The structure shown in Figure '7 comprises a 'resilient metal socket member 56, which is provided at its opposite ends with slotted portions providing a plurality of spring fingers 51 and 56, respectivelyr The spring fingers 5,8 are'provided with an enlarged arcuately curved portion indicated at 59, adapted to engage the head end "66- of a .terminal stud' member 62 secured in any suitable manner to a supporting bracket 63. A suitable garter spring 64 engages the free ends of the spring fingers 58 for.urging them into tight uniform pressure contact with the head end of the terminal 62.. The opposite end of the contact socket member 56 is adapted to receive the ball tip end 65 of a connecter rod 66 corresponding tothe connecter rod 21 of Fig ure 1, and the `spring fingers are inwardly rounded, as at 61, to receive a circularly coiled garter spring 69 for urging the fingers radially inwardly to provide a uniform pressure contact of each of the spring fingers 51 about the lateral surface of the ball tip 65. In this manner a selfaligning contact assembly is provided in which uniform contacting pressure is produced between each of the contact fingers andthe con- ,tact terminal and contact rod.

In Figurek 5 I have disclosed a modified form of connection, in which only two points of contact are required to effect electrical connection between a pair of spaced contacts.

Referring in detail to the structure shown in Figure 5, I provide a fixed contact Cmember 10, having a normally extending arm 12 supported upon a suitable supporting bracket 13. The contact member 16 is provided with a ball tip end 14, and is also provided with a longitudinally extending central passageway 15 receiving the internally threaded sleeve 16 which is mounted therein and which has an extending end portion projecting below the contact 10 and having a bevel gear member 11 keyed thereto. The gear 11 ,is driven by a second gear member 16 supported on a driving shaft 19.

The threaded shaft 16 is adapted to receive an externally threaded shaft which is reciprocated within the passageway 15 by rotation of the shaft 16, the shaft 89 having a suitable stop member 82 for limiting its downward movement within the passageway 15. The stop 62 slides in a suitable keyway 83 formed in the passageway 15 to prevent rotation of the shaft 86 and to provide for only longitudinal movement thereof. The upper end of shaft 80 has a socket 86 receiving the ball end 8|' of a pin 8l mounted 'for universal movement about the upper end of shaft At its upper end, the pin 8l is provided with a spider member 84 having radially extending arms 85 passing through suitable openings formed in a plurality of contact shoe members or bars 86,.,the outer lateral surface of the contact bars 86 being provided with tapered recesses ill re- R..- al.

ends against a stop plate 89 secured to the .outer y ends of the arms. This provides for resilient movement ofthe contact bars 86 inwardly and outwardly with respect to the spider 64, and also provides for resilient and uniform contact pressure of the bars against the ball tip end 90 of a contact member 92 fixed at a predetermined distance from the contact 10.

The lower ends of the contact bars 66 are also bars into contact engagement 'with thelball tip4 14 of the contact 10. The springs are'maintained in proper biasing position by an enclosing housing member 95 having suitably inset portions 96 forming spring seats for the springs-94. In this manner the lower ends of the contact bars 86 are biased inwardly into uniform contact engagecontacts 'l0 and 92 are silverplated in order to reduce the resistance to passage of current therethrough.

In the operation of the structure shown in Figure 5, in the position shown in this gure the contact bars 86 have been moved upwardly to provide for contacting engagement between the contacts 10 and 92. When it is desired to disconnect the electrical connection between4 these contacts, the shaft 19 is rotated by any suitable driving means to effect corresponding rotation of the sleeve 16. This results in threading of the externally threaded shaft 80 downwardly within the passageway 15, and results in corresponding movement of the contact bars 86 due to their engagement by the arms 85 of the spider 84 secured on the sleeve member, away from the ball tip 90,

disconnecting the contact 10 therefrom. At the same time, the lower ends of the contact bars `are moved downwardly past the ball -tip 14 of the contact '|0 until the contact bars 86 assume a position with the spider 84 disposed imme diately above the ball contact tip 'I4 of the contact 10, with thelower ends of the contact bars 86 being disposed about the lower cylindrical portion of the contact 10.

This provides a suitable clearance between the contacts 92 and 10, and at the same time pro- .duces wiping engagement of the inner surfaces of the contact bars 86 across the ball contact' tip 14, and also across the ball contact tip 90 when the bars are moved upwardly into contact en-v gaging position. This is extremely advantageous in providing a clean and positive contact between the ball contact tips and the contact bars, thus reducing the resistance through the connection. At the same time, the spring mounting of the contact bars 86 at their upper and lower ends assures that uniform contact pressure of each of the bars upon the lateral surface of the ball -contact tips '14 and 90 will be secured.

Obviously, the reciprocatory movement of the contact bars 86 might be secured by other means thanv the externally threaded shaft fitting in to the threaded sleeve 16, and I do not intend to limit my invention to this specific form of actuating mechanism, since a suitable plunger member might be employed for producing the same mode of operation. Further, even if a slight misalignment of the contacts 92 and 1.0 is present, the resilient mounting of the contact bars 86 upon the sleeve 80 insures that such misalignment will be accommodated, and that no uneven contact pressure Will be produced thereby.

Considering now in detail, the embodiment of the invention shown in Figures 8, 9 and 10, a contact stud is provided with an extending threaded portion |02 receiving a support member |03 threaded thereover and having a laterally extending portion |04 which receives a hollow metallic tube |05 threaded into a recess formed in the portion |04 of the member |03.

Within the lower end of the tube y|05 there is provideda bushing |06 which has an annular shoulder |01.seating on the bottom of the recess into which the tube |05 extends. The bushing |06 also has an extending cylindrical portion |08 whichextends into a suitable recess formed in the member |04. the bushing serving as a guide for the lower end |09 4of a threaded shaft ||0, which shaft at its-lower end is provided with a lhelical gear ||2 having bearing within a suitable supporting bracket member ||3. Suitable thrust washers ||4 are provided at opposite ends of the gear |I2, and the gear is adapted to be rotated by a second helical gear ||5 carried within suitable bushings ||6 extending into opposite ends of a' cylindrical'recess formed in the The bracket ||3 is also provided with oppositely `extending flanged shoulders I9,l which shoulders are adapted to receive suitable stud members securing the bracket ||3 to the portion |04 of the member |03. It will be noted that the bracket 3 may be rotated through a limited arc with respect to the member |04 in order to accommodate any slight misalignment between the mein-l ber |04 and the shaft |22 which carries the gear ||5.

The .shaft |22 extends outwardly of the bushings I6 and is provided with squaredend portions |23, one-of the end portions |23 receiving' a crank member |24 whereby the shaft |22 may be rotated in. opposite directions to produce corresponding rotation of the threaded shaft ||0.

'I'he upper end of the Itubular member 05 is' provided with a rounded external bead |25, which bead is adapted to form a suitable contact surface engaged by a plurality of contact shoes |26 having arcuate inner surfaces engaging about the bead |25 at the lower end thereof. The contact shoes |26 are also provided with concave recesses |21 for clearing the bead |25 when the shoesv are lowered. A plurality of spring members of arcuate cross-section, indicated at 28, are adapted to engage in suitably notched portions of the external surface of the members |26, being held in position by means of a polygonal band |29 surrounding the shoes and connected with the springs |28 by means of the adjustable threaded pin members |30 which have suitable seating engagement in the arched portions of the spring |28. This servos to urge the shoes |26 resiliently into engagement with the upper end of the tubular member |05 and to maintain equalized pressure between the shoes and the contact surface of the member 05.

The threaded shaft ||0 is provided with a spherical traveling nut |32 adapted to move upwardly and downwardly on the shaft ||0 by reason of the pin |33 guided in the keyway |34 formed in the internal surface of the member 05, whereby the nut |32 is prevented from rotation and threads upwardly and downwardly upon the shaft 0 as the shaft is rotated.

A suitable supporting sleeve |35 is providedat its lower end with a ball socket portion |36 welded or otherwise suitably secured thereto which engages about the spherical surface of the traveling nut |32 to provide for substantially universal movement of the sleeve |35 about the member 32. The socket portion 36 of the member |35 is suitably milled out as shown at |31 about the pin |33 to provide for this universal movement of the sleeve |35 about the traveling nut.

are adapted to receive radially extending blade r cam members |42, the members |42 extending radiallyoutwardly of the spider |40 and being suitably welded or otherwise secured in the milled out slots formed in the outer surface of the disc 40. The upper ends of the shoe membersl |26 are slotted, as indicated at |43, from the end longitudinally to a point below the extending arms |42 of the spider |40. Suitable leaf spring members |44 are mounted in vertically extending position on the external surface of the shoes |26 by means of bolts |45 threading into the shoes |26.

Retaining means |46 are carried by each of the arms |42 at the ends thereof, whereby the shoes |26 are supported upon the arms |42 by means of the bearing of the spring members on the upper edges of the arms |42. This provides for resilient mounting of the shoe members upon the spider |40, whereby the shoe members may move radially inwardly and outwardly under the pressure of springs |44 to be expanded or contracted, as desired.A

A hollow contact sleeve |50, or any other desired type of contact, is mounted in fixed position above the tube |05, and has an externally enclosing insulating member |52 carried thereabout and maintained in predetermined position with respect to the contact sleeve |50 by means of the lock nut |53 bearing-against the lower end of the insulator |52 and threaded onto the contact sleeve.

In the operation of the construction shown in Figures 8, 9 and 10, rotation of the crank |24 serves to rotate the shaft ||0, causing the nut 32 to travel longitudinally of this shaft. This results in downward movement of the member |35 from the position shown in Figure 8, which results in drawing of the upper ends |43 of the shoes |26 downwardly out of engagement with the contact end of the sleeve |50, thereby breaking contact between the contact |50 and the contact |00. This downward movement is accommodated by means of the recessed portions |21 oi.' the shoes |26 which t around the beaded portion |25 of the tubular member |05. The traveling nut |32 can move downwardly upon the shaft ||0 until the spider |40 rests upon the upper surface of the tubular member I 05. Inasmuch as the normal external diameter of the tubular member is substantially less than the beaded portion |25 thereof, or the external diameter of the contact sleevel50, the shoes will be expanded against the pressure of springs |28 and |43 when in the position shown in Figure 8. Consequently, upon downward movement, the shoes will contract, but cannot contract inwardly beyond the external diameter of the member |40 or the external diameter of the member |05. When the shoes have reached their lowermost position, the upper ends |43 thereof are contracted to a slight extent by reason of the pressure of springs |44. so that upon upward movement into switch closing position, the shoes will be spread radially as they come into engagement with the contact sleeve |50 due to the upwardly and outwardly flaring end portions |43 thereof, so that any slight misalignment of the contact |50 and the tubulare member |05 will be accommodated by the swinging movement of the sleeve |35 about the traveling nut |32, the sleeve having substantially universal movement about this nut so that as thecontact shoes are guided into engagement, the sleeve may rotate about the nut in any desired manner to accommodate any misalignment which may be present. 'Ihis swings the shoes in unison therewith. Also, by reason of the particular spring mounting disclosed, equalized contact pressure of each of the shoes against the stationary contact is provided, and the wiping action of the shoes across the contact surfaces serves to maintain these surfaces clean and bright.

In Figure 11, I have shown a modified type of contact structure in which two round ended cylindrical contact members, |66 and. |62, are adapted to receive therebetween a suitable contact sleeve formed of a plurality of contact shoes |63. Each of the contact shoes is provided at .opposite ends with inwardly beaded portions |64 `having substantially line contact engagement about the external surface of the members |60 and |62, whereby circular line contact of the shoes |63 with the external cylindrical surfaces of the members |60r and |62 is provided. Suitable tapered recesses |65 are formed in the external surfaces of each of the shoe members, and receive helically coiled springs |66 seating thereagainst and biased into position by means of a polygonal shaped sleeve member |61 maintaining the shoes in pressure engagement with the contacts |60 and |62. This provides for equalized contact pressure of the beaded portions |64 of each of the shoes against the contact sur.- n

faces.

In Figure l2, I have disclosed a second type of contact sleeve comprising a cylindrical member slotted longitudinally from the opposite ends in- 'Wardly past the central portion thereof, the

member |10 having slots 12 extending from one end thereof which Aare alternately spaced with respect to slots |13 extending frtm the opposite end thereof, the inner ends of the adjacent slots overlapping', as shown. The sleeve is adapted to fit over the rounded tips |14 and |15 of a pair of contact studs |16 and |11, re spectively. Due to the slotting of the sleeve |10, the fingers formed by the slots |12 and |13 are resiliently maintained in pressure engagement with the surface of the ball contact tips |14 and |15, thereby maintaining a substantially equalized contact pressure about each of these contact tips. The sleeve |10 or the contact as-` sembly comprising the shoes |63 of Figure 11 may be reciprocated with respect to the contacts in any desired manner to provide for closing and opening of the circuit therebetween.

It is therefore believed apparent that I have provided an electrical connecter adapted for use in situations in which contacts may be slightly misaligned, and which provides for the maintenance of equalized contact pressures and for,

the floating support of the contact member between the spaced contacts.

Having described my invention in accordance with the patent statutes, what I claim as new and desire to secure by Letters Patent is:

1. In an electrical connecter, a pair of spaced Contact studs, a full-floating contact structure mounted for universal movement about each of said studs, one of said contact structures Lbeing adapted to receive a connecting member Aendvvise therethrough, and a connecting member movable endwise' through said one contact structure into the other of said contact structures and having floating engagement between said contact structures. f

2. In an electrical connecter, a pair of spaced contact studs, each of said studs having a spring controlled contact structure mounted for universal movement thereon, one of said contact studs being adapted to receive a contact member endwise therethrough, and a contact member movable endwise through said one contact stud and into engagement between said contact structures to eiect electrical contact between said studs through said structures.

3. In an electrical connecter, a pair of spaced contact studs, a plurality of contact shoes for each of said studs, means for maintaining the shoes for each of said studs in equalized pressure contact with said respective studs, one of said studs being adapted to receive a connecting member endwise therethrough, and a connecting member movable endwise through said one stud into engagement between the respective shoes of each of said studs for effecting contact therebetween.

4. In an electrical connecter, a pair of spaced contact studs, one of said studs being adapted to receiv'e a connecting member endwise therethrough, a plurality of contact shoes for each of said studs, means for maintaining the shoes for each of said studs in equalized pressure contact with said respective studs, said means comprising an enclosing housing for said shoes havlng spring means biased between the interior of said housing and each of said shoes, and a connecting member movable endwise through one of said studs into engagement between the respective shoes of each of said studs for' eiecting contact therebetween.

5. In an electrical connecter, a pair oi.' spaced contact studs, one of said studs being adapted to receive a connecting member endwise therethrough, a plurality ofcontact shoes for each of said studs, means for maintaining the shoes for each of such studs in equalized pressure contact with said respective studs, said means for one of said studs comprising a spider member having radial arms receiving said shoes and spring means urging said shoes fcentrally toward said spider member, and a connecting member movable endwise through the other of said studs into engagement between the respective shoes of each of said studs for eiecting contact therebetween.

6. An electrical connecter comprising a rst terminal stud having a rounded head portion and adapted to receive a contact member endwise therethrough, a plurality of contact shoes mounted for conjoint universal movement about said head portion and deilning a contact-receiving opening, a second terminal stud spaced from said ilrst stud and having contact shoes mounted for conjoint universal movement thereabout, and a contactv member movable endwisel and axially of said rst terminal stud into engagement in said opening and with said contact shoes of said other stud.

7. An electrical connecter comprising a pair of spaced terminal studs having rounded head portions, a plurality ofcontact shoes mounted for universal movement about each of said head portions, one of said studs having an axial opening therethrough, and means movable through said 1 opening and into engagement between the respective contact shoes of each stud for eil'ecting electrical connection between saidl studs.

8. In combination, a pair Vo1' spaced contact studs, supporting brackets for each of said studs,

said contact studs being adapted to receive a contact member endwise therethrough, a plurality of contact shoes having substantially universal movement about each of said studs and extending outwardly of said studs, the shoes for one of said studs defining an outwardly ilaring cylindrical opening, the shoes for the other stud having inwardly extending contacting portions at urging said shoes together, a plurality of corresponding contact shoes mounted at one end about the head portion of the other stud and having outwardly aring surfaces at their opposite ends, corresponding spring means for said second plurality oi' shoes, and a rod-like member movable endwise through said one stud and the contacting portions of said first plurality of shoes and guided at its opposite end by said flaring surfaces into contact within said second plurality of shoes.

10. In combination, a rst terminal stud adap'ted to receive a connecting member endwise therethrough, contact shoes mounted for universal movement thereabout and extending outwardly of said stud, a second terminal stud, contact shoes mounted for universal movement about said second stud and extending outwardly toward said rst stud, a connecting member movable endwise through said rst stud and between said contact shoes carried thereby into engagement within the contact shoes carried by said second stud, and means for equalizing the contact pressure between each of said-shoes and the corresponding studs and between said shoes and said connecting member.

11. In combination, a pair of spaced contact studs, contact shoe structures mounted for universal movement about each of said studs and `Iextending toward each other, one of said studs 12. An electrical connecter comprising, in com- 4 bination, a pair of spaced apart contact members having convex spherical contact portions, a polygonally shaped' support member disposed substantially coaxially with said contact members, a contact shoe individual to each inner side of said polygonal support member and arranged and adapted to interconnect said contact members by contact engagement with said convex spherical contact portions thereof, and resilient means acting between said support member and said contact shoes for biasing them inwardly into contact engagement with said convex spherical contact portions oi' said contact members.

13. An electrical connecter comprising, in combination, a pair of spaced apart contact members having convex spherical contact portions, a polygonallyshaped support member disposed substantially coaxially with said contact aiaaeai contact members. one of said contact membersA being adapted to receive a connecting member` ner side of said polygonal support member and arranged and adapted to interconnect said contact members by contact engagement with said convex spherical contact portions thereof, means preventing detachment of said contact shoes from one of said contact members, said contact shoes being readily detachable from the other of said contact members, and resilient means individual to each of said contact shoes and acting between the same and the side of said polygonal support member individual thereto for biasing said contact shoes inwardly into contact engagement with said convex spherical contact portions of said contact members.

14. In an electrical connecter, a pair of spaced endwise therethrough, an assembly of contact ngers for each contact member, a connecting member movable endwise through said one contact member into engagement with the respective assemblies of contact iingers for effecting contact therebetween, and resilient means for maintaining equalized contact pressure between said assemblies of contact ngers, spaced contact members and connecting member for predetermined positions of misalignment of said spaced contact members.

CHARLES H. KOEHLER. 

